Recent questions tagged operating-system

114 votes

6 answers

3301

GATE CSE 2013 | Question: 39
A certain computation generates two arrays a and b such that $a[i] = f(i)$ for $0 \leq i < n$ and $b[i] = g(a[i])$ for $0 \leq i < n$. Suppose this computation is decomposed into two concurrent processes $X$ and $Y$ such that $X$ computes the array $a$ and $Y$ computes the ... EntryY(R, S) { V(S); P(R); } ExitX(R, S) { V(R); P(S); } EntryY(R, S) { V(S); P(R); }

A certain computation generates two arrays a and b such that $a[i] = f(i)$ for $0 \leq i < n$ and $b[i] = g(a[i])$ for $0 \leq i < n$. Suppose this computation is decompo...

28.3k views

Arjun asked Sep 24, 2014

60 votes

9 answers

3302

GATE CSE 2013 | Question: 34
A shared variable $x$, initialized to zero, is operated on by four concurrent processes $W, X, Y, Z$ as follows. Each of the processes $W$ and $X$ reads $x$ from memory, increments by one, stores it to memory, and then terminates. Each of the ... initialized to two. What is the maximum possible value of $x$ after all processes complete execution? $-2$ $-1$ $1$ $2$

A shared variable $x$, initialized to zero, is operated on by four concurrent processes $W, X, Y, Z$ as follows. Each of the processes $W$ and $X$ reads $x$ from memory, ...

22.3k views

Arjun asked Sep 24, 2014

80 votes

10 answers

3303

GATE CSE 2013 | Question: 29
Consider a hard disk with $16$ recording surfaces $(0-15)$ having $16384$ cylinders $(0-16383)$ and each cylinder contains $64$ sectors $(0-63)$. Data storage capacity in each sector is $512$ bytes. Data are organized cylinder-wise and the addressing ... cylinder number of the last sector of the file, if it is stored in a contiguous manner? $1281$ $1282$ $1283$ $1284$

Consider a hard disk with $16$ recording surfaces $(0-15)$ having $16384$ cylinders $(0-16383)$ and each cylinder contains $64$ sectors $(0-63)$. Data storage capacity in...

30.3k views

Arjun asked Sep 24, 2014

21 votes

6 answers

3304

GATE CSE 1999 | Question: 20-a
A certain processor provides a 'test and set' instruction that is used as follows: TSET register, flag This instruction atomically copies flag to register and sets flag to $1$. Give pseudo-code for implementing the entry and exit code to a critical region using this instruction.

A certain processor provides a 'test and set' instruction that is used as follows:TSET register, flagThis instruction atomically copies flag to register and sets flag to ...

4.5k views

Kathleen asked Sep 23, 2014

46 votes

4 answers

3305

GATE CSE 1999 | Question: 19
A certain computer system has the segmented paging architecture for virtual memory. The memory is byte addressable. Both virtual and physical address spaces contain $2^{16}$ bytes each. The virtual address space is divided into $8$ non-overlapping equal ... in page table entry for storing the aging information for the page? Assume that the page size is $512$ bytes.

A certain computer system has the segmented paging architecture for virtual memory. The memory is byte addressable. Both virtual and physical address spaces contain $2^{1...

25.2k views

Kathleen asked Sep 23, 2014

23 votes

6 answers

3306

GATE CSE 1999 | Question: 2-18, ISRO2008-46
Raid configurations of the disks are used to provide Fault-tolerance High speed High data density (A) & (B)

Raid configurations of the disks are used to provideFault-tolerance High speedHigh data density(A) & (B)

10.3k views

Kathleen asked Sep 23, 2014

75 votes

3 answers

3307

GATE CSE 1999 | Question: 2.12
Which of the following actions is/are typically not performed by the operating system when switching context from process $A$ to process $B$? Saving current register values and restoring saved register values for process $B$. Changing address translation tables. Swapping out the memory image of process $A$ to the disk. Invalidating the translation look-aside buffer.

Which of the following actions is/are typically not performed by the operating system when switching context from process $A$ to process $B$?Saving current register value...

27.6k views

Kathleen asked Sep 23, 2014

41 votes

4 answers

3308

GATE CSE 1999 | Question: 2.11
Which of the following is/are advantage(s) of virtual memory? Faster access to memory on an average. Processes can be given protected address spaces. Linker can assign addresses independent of where the program will be loaded in physical memory. Program larger than the physical memory size can be run.

Which of the following is/are advantage(s) of virtual memory?Faster access to memory on an average.Processes can be given protected address spaces.Linker can assign addre...

13.9k views

Kathleen asked Sep 23, 2014

36 votes

3 answers

3309

GATE CSE 1999 | Question: 2.10
A multi-user, multi-processing operating system cannot be implemented on hardware that does not support Address translation DMA for disk transfer At least two modes of CPU execution (privileged and non-privileged) Demand paging

A multi-user, multi-processing operating system cannot be implemented on hardware that does not supportAddress translationDMA for disk transferAt least two modes of CPU e...

12.7k views

Kathleen asked Sep 23, 2014

25 votes

2 answers

3310

GATE CSE 1999 | Question: 1.11, UGCNET-Dec2015-II: 44
System calls are usually invoked by using a software interrupt polling an indirect jump a privileged instruction

System calls are usually invoked by usinga software interruptpollingan indirect jumpa privileged instruction

12.0k views

Kathleen asked Sep 23, 2014

29 votes

6 answers

3311

GATE CSE 1999 | Question: 1.10
Which of the following disk scheduling strategies is likely to give the best throughput? Farthest cylinder next Nearest cylinder next First come first served Elevator algorithm

Which of the following disk scheduling strategies is likely to give the best throughput?Farthest cylinder nextNearest cylinder nextFirst come first servedElevator algorit...

11.2k views

Kathleen asked Sep 23, 2014

18 votes

2 answers

3312

GATE CSE 1999 | Question: 1.9
Listed below are some operating system abstractions (in the left column) and the hardware components (in the right column) ... 4 (A) - 3 (B) - 2 (C) - 4 (D) - 1 (A) - 4 (B) - 1 (C) - 2 (D) - 3

Listed below are some operating system abstractions (in the left column) and the hardware components (in the right column)$$\small \begin{array}{cl|cl}\hline \text{(A)}& ...

7.0k views

Kathleen asked Sep 23, 2014

57 votes

8 answers

3313

GATE CSE 2013 | Question: 16
Three concurrent processes $X$, $Y$, and $Z$ execute three different code segments that access and update certain shared variables. Process $X$ executes the $P$ operation (i.e., $wait$) on semaphores $a$, $b,$ and $c$; process $Y$ executes the $P$ operation on semaphores $b$, $c,$ and $d$; process ... $X:$ $P(a)P(b)P(c)$ $Y:$ $P(c)P(b)P(d)$ $Z:$ $P(c)P(d)P(a)$

Three concurrent processes $X$, $Y$, and $Z$ execute three different code segments that access and update certain shared variables. Process $X$ executes the $P$ operation...

17.1k views

Arjun asked Sep 23, 2014

63 votes

5 answers

3314

GATE CSE 2013 | Question: 10
A scheduling algorithm assigns priority proportional to the waiting time of a process. Every process starts with zero (the lowest priority). The scheduler re-evaluates the process priorities every $T$ time units and decides the next process ... is equivalent to the shortest-job-first algorithm. This algorithm is equivalent to the shortest-remaining-time-first algorithm.

A scheduling algorithm assigns priority proportional to the waiting time of a process. Every process starts with zero (the lowest priority). The scheduler re-evaluates th...

28.5k views

Arjun asked Sep 23, 2014

45 votes

6 answers

3315

GATE CSE 2005 | Question: 71
Suppose $n$ processes, $P_1, \dots P_n$ share $m$ identical resource units, which can be reserved and released one at a time. The maximum resource requirement of process $P_i$ is $s_i$, where $s_i > 0$. Which one of the following is a sufficient condition for ensuring that deadlock ... $\displaystyle{\sum_{i=1}^n} \: s_i < (m \times n)$

Suppose $n$ processes, $P_1, \dots P_n$ share $m$ identical resource units, which can be reserved and released one at a time. The maximum resource requirement of process ...

16.6k views

Kathleen asked Sep 22, 2014

35 votes

2 answers

3316

GATE CSE 2005 | Question: 22, ISRO2015-36
Increasing the RAM of a computer typically improves performance because: Virtual Memory increases Larger RAMs are faster Fewer page faults occur Fewer segmentation faults occur

Increasing the RAM of a computer typically improves performance because:Virtual Memory increasesLarger RAMs are fasterFewer page faults occurFewer segmentation faults occ...

41.7k views

Kathleen asked Sep 22, 2014

23 votes

5 answers

3317

GATE CSE 2005 | Question: 21
What is the swap space in the disk used for? Saving temporary html pages Saving process data Storing the super-block Storing device drivers

What is the swap space in the disk used for?Saving temporary html pagesSaving process dataStoring the super-blockStoring device drivers

19.9k views

Kathleen asked Sep 22, 2014

36 votes

4 answers

3318

GATE CSE 2005 | Question: 20
Normally user programs are prevented from handling I/O directly by I/O instructions in them. For CPUs having explicit I/O instructions, such I/O protection is ensured by having the I/O instruction privileged. In a CPU with memory mapped I/ ... /O protection is ensured by a hardware trap I/O protection is ensured during system configuration I/O protection is not possible

Normally user programs are prevented from handling I/O directly by I/O instructions in them. For CPUs having explicit I/O instructions, such I/O protection is ensured by ...

11.4k views

Kathleen asked Sep 22, 2014

45 votes

7 answers

3319

GATE CSE 2005 | Question: 19
Which one of the following is true for a CPU having a single interrupt request line and a single interrupt grant line? Neither vectored interrupt nor multiple interrupting devices are possible Vectored interrupts are not possible ... and multiple interrupting devices are both possible Vectored interrupts are possible but multiple interrupting devices are not possible

Which one of the following is true for a CPU having a single interrupt request line and a single interrupt grant line?Neither vectored interrupt nor multiple interrupting...

21.0k views

Kathleen asked Sep 22, 2014

48 votes

5 answers

3320

GATE CSE 2009 | Question: 51
A hard disk has $63$ sectors per track, $10$ platters each with $2$ recording surfaces and $1000$ cylinders. The address of a sector is given as a triple $\langle c, h, s \rangle$, where $c$ is the cylinder number, $h$ is the surface number ... $\langle 400, 16, 29 \rangle$ corresponds to sector number: $505035$ $505036$ $505037$ $505038$

A hard disk has $63$ sectors per track, $10$ platters each with $2$ recording surfaces and $1000$ cylinders. The address of a sector is given as a triple $\langle c, h, s...

19.5k views

Kathleen asked Sep 22, 2014

35 votes

4 answers

3321

GATE CSE 2009 | Question: 34
A multilevel page table is preferred in comparison to a single level page table for translating virtual address to physical address because It reduces the memory access time to read or write a memory location. It helps to reduce the size of ... is required by the translation lookaside buffer. It helps to reduce the number of page faults in page replacement algorithms.

A multilevel page table is preferred in comparison to a single level page table for translating virtual address to physical address becauseIt reduces the memory access ti...

14.4k views

Kathleen asked Sep 22, 2014

61 votes

13 answers

3322

GATE CSE 2009 | Question: 33
The enter_CS() and leave_CS() functions to implement critical section of a process are realized using test-and-set instruction as follows: void enter_CS(X) { while(test-and-set(X)); } void leave_CS(X) { X = 0; } In the above solution, $X$ is a memory location ... at the same time Which of the above statements are TRUE? (I) only (I) and (II) (II) and (III) (IV) only

The enter_CS() and leave_CS() functions to implement critical section of a process are realized using test-and-set instruction as follows:void enter_CS(X) { while(test-an...

24.8k views

Kathleen asked Sep 22, 2014

36 votes

3 answers

3323

GATE CSE 2009 | Question: 32
In the following process state transition diagram for a uniprocessor system, assume that there are always some processes in the ready state: Now consider the following statements: If a process makes a transition $D$, it would result in another process making ... -preemptive scheduling. Which of the above statements are TRUE? I and II I and III II and III II and IV

In the following process state transition diagram for a uniprocessor system, assume that there are always some processes in the ready state:Now consider the following sta...

18.6k views

Kathleen asked Sep 22, 2014

20 votes

3 answers

3324

GATE CSE 2009 | Question: 31
Consider a disk system with $100$ cylinders. The requests to access the cylinders occur in following sequence: $4, 34, 10, 7, 19, 73, 2, 15, 6, 20$ Assuming that the head is currently at cylinder $50$ ... seek time first policy is used? $95 \;\text{ms}$ $119\;\text{ms}$ $233\;\text{ms}$ $276\;\text{ms}$

Consider a disk system with $100$ cylinders. The requests to access the cylinders occur in following sequence:$4, 34, 10, 7, 19, 73, 2, 15, 6, 20$Assuming that the head i...

8.4k views

Kathleen asked Sep 22, 2014

67 votes

10 answers

3325

GATE CSE 2009 | Question: 30
Consider a system with $4$ types of resources $R1$ ($3$ units), $R2$ ($2$ units), $R3$ ($3$ units), $R4$ ($2$ units). A non-preemptive resource allocation policy is used. At any given instance, a request is not entertained if it cannot be ... deadlock Only $P1$ and $P2$ will be in deadlock Only $P1$ and $P3$ will be in deadlock All three processes will be in deadlock

Consider a system with $4$ types of resources $R1$ ($3$ units), $R2$ ($2$ units), $R3$ ($3$ units), $R4$ ($2$ units). A non-preemptive resource allocation policy is used....

34.0k views

Kathleen asked Sep 22, 2014

32 votes

2 answers

3326

GATE CSE 2009 | Question: 10
The essential content(s) in each entry of a page table is / are Virtual page number Page frame number Both virtual page number and page frame number Access right information

The essential content(s) in each entry of a page table is / areVirtual page numberPage frame numberBoth virtual page number and page frame numberAccess right information

11.5k views

Kathleen asked Sep 22, 2014

20 votes

5 answers

3327

GATE CSE 2009 | Question: 9, ISRO2016-52
In which one of the following page replacement policies, Belady's anomaly may occur? FIFO Optimal LRU MRU

In which one of the following page replacement policies, Belady's anomaly may occur?FIFOOptimalLRUMRU

8.4k views

Kathleen asked Sep 22, 2014

16 votes

4 answers

3328

GATE CSE 2007 | Question: 82
A process has been allocated $3$ page frames. Assume that none of the pages of the process are available in the memory initially. The process makes the following sequence of page references (reference string): $\mathbf{1, 2, 1, 3, 7, 4, 5, 6, 3, 1}$ If optimal page replacement policy is used, how many page faults occur for the above reference string? $7$ $8$ $9$ $10$

A process has been allocated $3$ page frames. Assume that none of the pages of the process are available in the memory initially. The process makes the following sequence...

9.4k views

Kathleen asked Sep 21, 2014

57 votes

10 answers

3329

GATE CSE 2007 | Question: 58
Two processes, $P1$ and $P2$, need to access a critical section of code. Consider the following synchronization construct used by the processes: /* P1 */ while (true) { wants1 = true; while (wants2 == true); /* Critical ... waiting. It requires that processes enter the critical section in strict alteration. It does not prevent deadlocks, but ensures mutual exclusion.

Two processes, $P1$ and $P2$, need to access a critical section of code. Consider the following synchronization construct used by the processes:/* P1 */ while (true) { wa...

27.5k views

Kathleen asked Sep 21, 2014

25 votes

2 answers

3330

GATE CSE 2007 | Question: 57
A single processor system has three resource types $X, Y$ and $Z$, which are shared by three processes. There are $5$ units of each resource type. Consider the following scenario, where the column alloc denotes the number of units of each resource type allocated to each ... $P0$ $P1$ $P2$ None of the above, since the system is in a deadlock

A single processor system has three resource types $X, Y$ and $Z$, which are shared by three processes. There are $5$ units of each resource type. Consider the following ...

10.9k views

Kathleen asked Sep 21, 2014

Page:

« prev
1
...
106
107
108
109
110
111
112
113
114
next »